Pushbutton tuner clutch mechanism

ABSTRACT

A clutch mechanism for a pushbutton tuner effects operative driving engagement between a depressible adjusting shaft and a tuning shaft, both axially aligned and rotatable in a housing. The adjusting shaft is accessible externally of the housing and has a housing-enclosed part which is tubular in shape with spaced longitudinally extending grooves in the tube walls. A springurged tubular connecting member having spaced protrusions is received within the adjusting member tube part, with the protrusions riding within the grooves, and at a base thereof the tube bore walls are contoured to mate with projections on the tuning shaft upon alignment therewith. A caplike member encloses the tube part open end, and it is spring urged to move the clutch mechanism to its undepressed condition. Upon depression of the adjusting shaft the connecting member is moved toward the projections, and if the projections and contoured walls are not aligned, the connecting member is forced to slide within the tube, compressing the spring active thereon. Upon rotation of the adjusting shaft, the projections and the contoured walls align, and the spring acts on the connecting member so that the projections and walls come into operative driving engagement. Continued rotation of the adjusting shaft in either direction effects adjustment of the tuning shaft without lost motion. Holding means maintains the adjusting shaft in its depressed condition, and disengagement of that holding means permits the second spring to return the adjusting shaft to its undepressed condition.

United States Patent [72] Inventor Masatsugu Aoki Tokyo, Japan [21] Appl. No. 64,198 [22] Filed Aug. 17, 1970 [45] Patented Nov. 23, 1971 73] Assignee Alps Electric Co., Ltd.

Tokyo, Japan [32] Priority Oct. 23, I969 [33] Japan 1 44/ 100729 [54] PUSHBU 1'1 0N TUNER CLUTCH MECHANISM 9 Claims, 8 Drawing Figs.

[52] US. Cl 192/95, 74/10.27, 334/7 [51] Int. Cl. Fl6d 19/00 [50] Field ofSearch 192/95, 67 R, 108; 74/1027; 334/7 [5 6] References Cited UNITED STATES PATENTS 2,899,841 8/1959 Melloy 192/67 X Primary Examiner-Milton Kaufman Attorney-James and Franklin ABSTRACT: A clutch mechanism for a pushbutton tuner effects operative driving engagement between a depressible adjusting shaft and a tuning shaft, both axially aligned and rotatable in a housing. The adjusting shaft is accessible externally of the housing and has a housing-enclosed part which is tubular in shape with spaced longitudinally extending grooves in the tube walls. A spring-urged tubular connecting member having spaced protrusions is received within the adjusting member tube part, with the protrusions riding within the grooves, and at a base thereof the tube bore walls are contoured to mate with projections on the tuning shaft upon alignment therewith. A caplike member encloses the tube part open end, and it is spring urged to move the clutch mechanism to its undepressed condition. Upon depression of the adjusting shaft the connecting member is moved toward the projections, and if the projections and contoured walls are not aligned, the connecting member is forced to slide within the tube, compressing the spring active thereon. Upon rotation of the adjusting shaft, the projections and the contoured walls align, and the spring acts on the connecting member so that the projections and walls come into operative driving engagement. Continued rotation of the adjusting shaft in either direction effects adjustment of the tuning shaft without lost motion. Holding means maintains the adjusting shaft in its depressed condition, and disengagement of that holding means permits the second spring to return the adjusting shaft to its undepressed condition.

N viii- 35-4 i-ww PATENIEDNBV 23 an 3.621 362 SHEEI 1 or 2 MMM INVENTOR.

The present invention relates to a clutch mechanism for a pushbutton tuner in which the buttons are rotatable after depression for purposes of tuning adjustment.

A pushbutton tuner, adapted for use in radios and like devices, must remain operable through repeated actuations. If the individual buttons, when depressed, must be clutched to a tuning shaft, the clutch mechanism which forms a part thereof must accommodate a large number of such depressions without failure.

Another highly desirable characteristic of a pushbutton tuner clutch mechanism, is the ability, once the adjusting shaft is engaged with the tuning member, to provide continuous fine tuning, irrespective of direction change, and without substantial lost motion. This makes station changing and fine tuning far less burdensome.

A further advantageous aspect of a pushbutton tuner is the provision of a clutch mechanism the structure of which is simple and easy to assemble.

Accordingly, the present invention provides a tubular adjusting shaft which receives therein a spring-urged tubular connecting member. Depression and rotation of the adjusting shaft effects a mating engagement of projections on a rotatable tuning member with walls of the connecting member tube bore which are contoured to mate with the projections upon alignment therewith. Once the adjusting shaft and the tuning shaft are operatively engaged, the tuning shaft can be continuously adjusted, irrespective of direction change, and without substantial lost motion.

It is a prime object of the present invention to provide a pushbutton tuner clutch mechanism which .reliably effects operative driving engagement between adjusting and tuning members through repeated manipulations.

It is another object of the present invention to provide a pushbutton tuner clutch mechanism which permits adjustment of the tuning member without substantial lost motion and irrespective of tuning direction change.

A further object of the present invention is the provision of a clutch mechanism characterized by ease of assembly, simplicity of structure, and adaptability for mass production.

The above objects are achieved by a clutch mechanism construction which provides a depressible adjusting shaft with a tubular inner end having longitudinal spaced grooves formed in the tube walls. A resilient spring is received in the tube and acts on a tubular connecting member, which, upon depression of the adjusting shaft forms an operative driving connection between that shaft and a tuning member. The connecting member has spaced projections adapted to slidably ride within the grooves in the tube, and its bore is adapted to receive the tuning member therewithin, the bore walls being contoured to mate with projections on the tuning member upon alignment therewith. Holding means comprising a cam formed on the adjusting shaft and a cam follower which contacts a cam shoulder on the adjusting shaft maintains the adjusting shaft in its depressed condition to enable continuous adjustment of the tuning member. A caplike member encloses the tube part open end and is acted upon by a spring which tends to urge the adjusting member to its undep'ressed condition. Upon depression of the adjusting shaft, the connecting member is moved toward the projections on the tuning member. If the projections are not aligned with the contoured bore walls of the connecting member, the latter is urged inwardly relative to the adjusting shaft, the biasing spring active therein being compressed by the sliding of the connecting member within the adjusting shaft. Rotation of the adjusting shaft causes the projections and'contoured walls to align and the compressed spring urges the connecting member to move outwardly into driving connection with the tuning member. Thereafter, the adjusting shaft can be rotated, thereby to adjust the tuning member, irrespective of direction change, and without lost motion.

To the accomplishment of the above, and to such other objects as may hereinafter appear, the present invention relates to a clutch mechanism for pushbutton tuners, as defined in the appended claims, and as described in the specification taken together with the accompanying drawings in which:

FIG. 1 is a front view of a device such as a radio utilizing a plurality of pushbutton tuners employing the clutch mechanism of the instant invention;

FIG. 2 is a partially cross-sectioned view of a representative pushbutton tuning device employing the clutch mechanism of the invention;

FIG. 3A is a cross-sectioned view of the clutch mechanism taken along the line 3A3A of FIG. 2;

FIG. 3B is a cross-sectioned view of the clutch mechanism taken along the line 3B-3B of FIG. 2;

FIG. 4 is an exploded perspective view of the parts which form the operative driving connection;

FIG. 5A is a partially cross-sectioned view of the clutch mechanism employed in a representative tuner;

FIG. 5B is a partially cross-sectioned view showing engagement of the projections with the contoured walls; and

FIG. 5C is a partially cross-sectioned view showing depression of the adjusting member and misalignment of the contoured walls with the projections.

Referring to FIG. 1, a device 10 such as a radio or the like may incorporate a single pushbutton tuner as employing the clutch mechanism hereinafter described, or may utilize a multiple of such mechanisms depending upon the needs of the specific device with which it is to be used. These pushbutton tuners 10 are adaptable for channel selecting, fine tuning, volume control, or in general, adjustment of any other parameter. They are characterized by having first to depress an adjusting member to operatively effect the necessary adjustment.

Referring to FIGS. 2 and 4, the clutch mechanism 12 of the present invention is mounted within a housing 14 which comprises front and rear walls 16 and 18. In the embodiment here shown, a switching member I9 is rotatably mounted within an opening 20 in the side wall 16. That switching shaft may be used as an on/ofi control, or may have any other function as required by the considered device. Its connection and use forms no part of the present invention, and hence the structure associated with the member 19 is not here illustrated. An adjusting member 21 in the nature of a shaft is rotatably mounted within the switch member 19. The inner section 22 of that adjusting shaft is tubular in shape, and has spaced longitudinal grooves 24 formed in the walls of that tube section 22. The adjusting member 21 is in axial alignment with a tuning member 26 which is rotatable in the housing 14. Upon completion of an operative driving connection between the adjusting member 21 and the tuning member 26, as hereinafter described, rotation of that adjusting member 21 in any direction effects adjustment of that tuning member 26.

To effect the connection between the adjusting member 21 and the tuning member 26, a connecting member 30, which is tubular in shape and the outer diameter of which is slightly smaller than the inner diameter of the tube section 22 is provided, the connecting member 30 being axially slidably received in the tube section 22 and having spaced protrusions 32 which are adapted to slidably ride within the grooves 24. At base 37 of that connecting member the tube opening or bore 36 has contoured walls 38 adapted to mate with similarly shaped projections 39 on the tuning member 26. A compression spring 40 is received within the tube part 22 and bears against the connecting member 30, tending to urge the latter axially out from the former. Rotation of the adjusting shaft 21 is directly transmitted to the connecting member 30 by the groove-projection engagement without substantial lost motion. As noted in FIGS. 2, SA, 53 and 5C, the adjusting member 2], connecting member 30 and tuning member 26 are all axially aligned.

It is necessary to provide the clutch mechanism with means to (a) ensure the connecting member 30 does not slide out of the tube section 22, and (b) return the adjusting shaft 21 to its undepressed condition at the convenience of the user. Both functions are accomplished by a hollow caplike member 42 having an inner diameter which closely corresponds to the outer diameter of tube section 22 of the adjusting shaft 21, the member 42 being telescoped over connecting member tube open end 43 after the connecting member 30 is received therewithin. The cap 42 comprises a collar 44 and a base 46 having an opening 48 which registers with and is somewhat smaller than bore 36. A second compression spring 50 is active between the inner surface of wall 18 and the collar 44 of member 42 to constantly urge the latter, and consequently the adjusting shaft 21, outwardly toward the undepressed condition.

It is highly desirable for the clutch mechanism to provide means to maintain the adjusting shaft in its depressed condition. This is accomplished by a holding means which comprises a cam 52 formed on the adjusting shaft 21 and terminating in the shoulder 54 adjacent the inner wall 16 (when the adjusting shaft 21 is in its undepressed condition), and a resilient cam follower 56 which is fixed to wall 18 and has a vertically depending section 58 which rides along cam 52. Upon depression of connecting member 21, cam follower 56 is driven upwardly until it reaches the end of that cam, whereupon it is urged downwardly by the leaf spring 60 into contact with the shoulder 54. The outward urging of spring 50 causes the shoulder 54 to bear against follower section 58. This engagement of the section 58 and the shoulder 54 maintains the adjusting shaft 21 in its depressed condition until the cam follower 56 is moved (by any appropriate mechanism) to disconnect the section 58 from the shoulder 54, thereby to pennit the spring 50 to urge the cap 42 and consequently the adjusting member 21 to its undepressed condition.

Reference is now made to FIGS. A, 5B and 5C, so as to describe the clutch mechanism in its sequential operating positions. FIG. 5A shows the adjusting shaft 21 in its undepressed condition, in which the contoured walls 38 are initially aligned with the projections 39. Therefore, upon depression of the adjusting shaft 21 the member 58 engages behind the shoulder 54, maintaining the depressed position of that shaft, and the walls 38 and projections 39 are mated in an operative driving engagement (FIG. 5B). The adjusting member 21 can then be rotated in any direction, which rotation will effect adjustment of the tuning member 26 without lost motion. In FIG. 5C the clutch mechanism is illustrated in a position in which the walls 38 and the projections 39 are initially misaligned. In this position depression of the adjusting member 21 will again be maintained by contact between the section 58 and the shoulder 54. However, the walls 38 and the projections 39 will not engage. in this position the base 37 contacts the projections 39 causing the connecting member to slide inwardly (with respect to the adjusting member 21) thereby to compress the spring 40. In this condition, if the adjusting member 21 is then rotated, the walls 38 and projections 39 will align, and the spring 40, tending to release its compression, will urge the connecting member 30 outwardly so that the walls 38 and projections 39 mate in an operative driving engagement. Then, as described in reference to FIG. 5A, rotation of the adjusting member 21 provides continuous and uninterrupted adjustment of the tuning member 26, without lost motion, and irrespective of direction change.

From the foregoing description, it is evident that the clutch mechanism herein described provides a reliable operative connection between the adjusting member 21 and the tuning member 26, which permits continuous and uninterrupted adjustment of that tuning member irrespective of direction change, and without lost motion. The simplicity of the principal components and their ease of assembly make this mechanism well suited for mass production, and for use in devices such as radios employing a plurality of pushbutton tuners.

While but a single embodiment of the present invention is herein disclosed, it will be appreciated that many variations may be made in the details thereof, without departing from the spirit and scope of the invention, as defined in the appended claims.

lclaim:

1. For use with a tuner comprising a housing, an adjustable tuning member rotatable in said housing and an adjusting member mounted in and accessible externally of said housing, said adjusting member being movable in a first manner from undepressed to depressed positions and vice versa respectively to effect and disable an operative driving connection between said adjusting and tuning members, said adjusting member being movable in a second manner to rotatably adjust said tuning member upon effectuation of said operative driving connection therebetween; an assembly to efiect said operative driving connection between said adjusting member and said tuning member comprising a projection on said tuning member, a connecting member mounted on said adjusting member with lost motion in said first manner of movement and movable with said adjusting member in said second manner of movement, said connecting member having openings spaced from said tuning member projection when said adjusting member is in its undepressed position and adapted to mate with said tuning member projection upon alignment therewith when said adjusting member is in its depressed position, and first yieldable urging means active to urge said connecting member to move on said adjusting member in said first manner of movement toward said tuning member, whereby upon depression, and rotation if necessary, of said adjusting member, said connecting member is moved into operative driving connection with said tuning member.

2. The assembly of claim 1, comprising second urging means active on said adjusting member and said housing to urge said adjusting member toward said undepressed position.

3. The assembly of claim 2, in which said adjusting member comprises a shaft having a tubular inner portion, said first urging means is received within said tubular portion, said shaft has a longitudinal groove in the wall ofsaid tube, and said connecting member is received within said tubular portion and has a projection slidably received in said groove.

4. The assembly of claim 3, in which said connecting member has a tubular portion, said opening being formed in the radially inner surface of said connecting member tubular portion, said tuning member having a first part axially slidably received in said connecting member and having a'second part carrying said projection which is out of, or in, said connecting member tubular part depending on whether said adjusting member and the connecting member carried thereby are in said undepressed or depressed conditions respectively.

5. The assembly of claim 2, in which said connecting member has a tubular portion, said opening being formed in the radially inner surface of said connecting member tubular portion, said tuning member having a first part axially slidably received in said connecting member tubular portion, said tuning member having a first part axially slidably received in said connecting member tubular portion for all positions of said connecting member and having a second part carrying said projection which is out of, or in, said connecting member tubular part depending on whether said adjusting member and the connecting member carried thereby are in said undepressed or depressed conditions respectively.

6. The assembly of claim 2, in which said second urging means comprises an abutment member operatively mounted on said adjusting member and having a resilient member active between said housing and said abutment in a direction toward said undepressed position of said adjusting member, thereby to urge said adjusting member to said undepressed position.

7. The assembly of claim 1, in which said adjusting member comprises a shaft having a tubular inner portion, said first urging means is received within said tubular portion, said shaft has a longitudinal groove in the wall of said tube, and said connecting member is received within said tubular portion and has a projection slidably received in said groove.

8. The assembly of claim 7, in which said connecting member has a tubular portion, said opening being formed in the radially inner surface of said connecting member tubular portion, said tuning member having a first part axially slidably received in said connecting member tubular portion for all positions of said connecting member and having a second part carrying said projection which is out of. or in, said connecting 

1. For use with a tuner comprising a housing, an adjustable tuning member rotatable in said housing and an adjusting member mounted in and accessible externally of said housing, said adjusting member being movable in a first manner from undepressed to depressed positions and vice versa respectively to effect and disable an operative driving connection between said adjusting and tuning members, said adjusting member being movable in a second manner to rotatably adjust said tuning member upon effectuation of said operative driving connection therebetween; an assembly to effect said operative driving connection between said adjusting member and said tuning member comprising a projection on said tuning member, a connecting member mounted on said adjusting member with lost motion in said first manner of movement and movable with said adjusting member in said second manner of movement, said connecting member having openings spaced from said tuning member projection when said adjusting member is in its undepressed position and adapted to mate with said tuning member projection upon alignment therewith when said adjusting member is in its depressed position, and first yieldable urging means active to urge said connecting member to move on said adjusting member in said first manner of movement toward said tuning member, whereby upon depression, and rotation if necessary, of said adjusting member, said connecting member is moved into operative driving connection with said tuning member.
 2. The assembly of claim 1, comprising second urging means active on said adjusting member and said housing to urge said adjusting member toward said undepressed position.
 3. The assembly of claim 2, in which said adjusting member comprises a shaft having a tubular inner portion, said first urging means is received within said tubular portion, said shaft has a longitudinal groove in the wall of said tube, and said connecting member is received within said tubular portion and has a projection slidably received in said groove.
 4. The assembly of claim 3, in which said connecting member has a tubular portion, said opening being formed in the radially inner surface of said connecting member tubular portion, said tuning member having a first part axially slidably received in said connecting member and having a second part carrying said projection which is out of, or in, said connecting member tubular part depending on whether said adjusting member and the connecting member carried thereby are in said undepressed or depressed conditions respectively.
 5. The assembly of claim 2, in which said connecting member has a tubular portion, said opening being formed in the radially inner surface of said connecting member tubular portion, said tuning member having a first part axially slidably received in said connecting member tubular portion, said tuning member having a first part axially slidably received in said connecting member tubular portion for all positions of said connecting member and having a second part carrying said projection which is out of, or in, said connecting member tubular part depending on whether said adjusting member and the connecting member carried thereby are in said undepressed or depressed conditions respectively.
 6. The assembly of claim 2, in which said second urging means comprises an abutment member operatively mounted on said adjusting member and having a resilient member active between said housing and said abutment in a direction toward said undepressed position of said adjusting member, thereby to urge said adjusting member to said undepressed position.
 7. The assembly of claim 1, in which said adjusting member comprises a shaft having a tubular inner portion, said first urging means is received within said tubular portion, said shaft has a longitudinal groove in the wall of said tube, and said connecting member is received within said tubular portion and has a projection slidably received in said groove.
 8. The assembly of claim 7, in which said connecting member has a tubular portion, said opening being formed in the radially inner surface of said connecting member tubular portion, said tuning member having a first part axially slidably received in said connecting member tubular portion for all positions of said connecting member and having a second part carrying said projection which is out of, or in, said connecting member tubular part depending on whether said adjusting member and the connecting member carried thereby are in said undepressed or depressed conditions respectively.
 9. The assembly of claim 1, in which said connecting member has a tubular portion, said opening being formed in the radially inner surface of said connecting member tubular portion, said tuning member having a first part axially slidably received in said connecting member tubular portion, said tuning member having a first part axially slidably received in said connecting member tubular portion for all positions of said connecting member and having a second part carrying said projection which is out of, or in, said connecting member tubular part depending on whether said adjusting member and the connecting member carried thereby are in said undepressed or depressed conditions respectively. 